Radio frequency IDs (RFIDs), like contactless smart cards, store credential information that can be used later to gain access to an asset. When presented to a reader/interrogator the smart card transmits the stored credential information for verification by the reader/interrogator. The reader/interrogator processes the credential information and determines if the smart card being presented is a valid smart card. If the reader/interrogator determines that the credential information on the smart card is valid then the reader/interrogator sends the initiates any number of actions allowing the holder of the smart card access to a particular asset.
NFC is a communication method that is showing great promise for communication between devices at short range. NFC may be regarded as the same protocol that is used by contactless smart cards working at 13.56 MHz. Several companies are in the process of announcing mobile phones that incorporate an NFC chip. The communication protocol of a typical NFC chip can be seen for instance in Short Form Specification of the PN511-Transmission module, February 2004 from Philips Semiconductors, which is herein incorporated by reference in its entirety.
The protocol used in NFC can vary depending on the mode that the chip and reader/interrogator are in. For example, if an active NFC mode is used, both a reader/interrogator and target are using their own radio frequency (RF) field to enable communication between each other. A reader/interrogator is powered to generate an RF filed of a particular frequency, for instance at 13.56 MHz. The target has its own power supply for digital processing and communications. When the target receives a communication from a reader/interrogator, the target uses its own power supply to generate another RF field to answer the reader/interrogator. Communications can occur back and forth between the reader/interrogator and target. Alternatively, if a passive NFC mode is implemented, the target answers to a reader/interrogator command in a load modulation scheme. The target is not powered to generate its own RF field. Rather, the target uses energy from the RF created by the reader/interrogator to create its RF field and reply to be sent back to the reader/interrogator.
If the NFC chip is coupled with a micro-processor, the chip may act like smart cards or the like where communication between a reader and card are performed to gain access to an asset. Typically a mobile phone includes a battery and the NFC chip can be powered by that battery. If the chip derives power from the mobile phone battery, the NFC chip may communicate with an reader/interrogator according to the active protocol described above. Alternatively, the NFC chip can communicate with a reader/interrogator in a passive mode. This will eliminate the need for the chip to be powered by the battery of a mobile phone, which may increase the life of the battery.
In most global system for mobile communication (GSM) devices, e.g., mobile phones, there is a Subscriber Identification Module (SIM) that is a secure memory containing all of the owner's account information, as well as space available for additional applications such as an electronic purse for e-commerce. This memory is accessible from outside of the mobile device, i.e., remotely. Mobile devices carry a secure memory much like smart cards or the like and the new applications in NFC protocols enable the mobile device to perform functions like smart cards. The ability to have a mobile device also operate as a smart card creates a variety of new applications for the device.
Typical smart cards are a small, usually credit card shaped, device that contains at least a memory device for storing information and a transceiver to communicate with a reader/interrogator. The reader/interrogator communicates through the transceiver on the smart card to access the stored information. The reader/interrogator may simply read the information, load the information into the memory device or modify existing data in the memory device. For example, if the owner of a smart card uses a smart card containing financial information to make a purchase, the reader/interrogator can read the information including the owner's identity and the availability of funds. The reader/interrogator can also deduct the purchase amount from the available funds if it has writing capabilities. Further, the reader/interrogator can store transaction data on the smart card including the time and location of the transaction in addition to the identity of the reader/interrogator.
Smart cards have a variety of uses and can be utilized in any transaction that involves the exchange of data or information between individuals and an institution. For example, smart cards can be used to store information including medical records, financial information, vehicle maintenance information, pet information, and a virtually limitless variety of other information traditionally printed on paper or plastic or stored on cards having a magnetic stripe or an optical bar code. Smart card technology has been particularly useful in banking systems and other financial transaction systems. Furthermore, smart cards have been widely used in access control systems. For example, an reader/interrogator may control doors that provide access to particular assets. The reader/interrogator only allows qualified individuals carrying smart cards, with proper credentials loaded thereon, access through control doors.
In a conventional access control system, the door reader/interrogators positioned at ingress/egress points are connected to a control panel. This control panel is kept up to date with the authorized codes corresponding to persons with authorized access to the location. When activity occurs, the control panel is updated with the activity information. For example, if the activity related to access gained through a particular door, the door and potentially the person who gained access are stored in the control panel log. Also, if the activity related to a financial transaction, the information relating to the transaction including amount and who performed the transaction are sent and stored at the control panel. There are, however, circumstances in which control panels associated with remote locations that are not regularly updated. If a person's status changes from authorized to unauthorized, it might take a relatively long time for the control panel associated with a remote door to get the message and bar the credential associated with this person from access. Furthermore, typical access control systems are limited in that control panels, either localized or central, are the only source that tracks, logs, and monitors the activity associated with a given access point. When entries take place in these conventional access control systems, the information is sent to the control panel where it stays. If someone would like to be aware of activity associated with the access control system they are usually required to physically go to the control panel itself.